count {arkhe}

Count Values Using a Predicate

Description

Counts values by rows/columns using a predicate function.

Usage

count(x, ...)

## S4 method for signature 'data.frame'
count(x, f, margin = 1, negate = FALSE, na.rm = FALSE, ...)

## S4 method for signature 'matrix'
count(x, f, margin = 1, negate = FALSE, na.rm = FALSE, ...)

Arguments

x

An R object (should be a matrix or a data.frame).

...

Further arguments to be passed to f.

f

A predicate function.

margin

A length-one numeric vector giving the subscripts which the function will be applied over (1 indicates rows, 2 indicates columns).

negate

A logical scalar: should the negation of f be used instead of f?

na.rm

A logical scalar: should NA values be stripped before the computation proceeds?

Value

A numeric vector.

Author(s)

N. Frerebeau

See Also

Other data preparation tools: append(), assign(), compact(), detect(), discard(), get(), keep(), seek()

Examples

## Create a data matrix
X <- matrix(sample(1:10, 25, TRUE), nrow = 5, ncol = 5)

## Add NA
k <- sample(1:25, 3, FALSE)
X[k] <- NA
X

## Count missing values in rows
count(X, f = is.na, margin = 1)
## Count non-missing values in columns
count(X, f = is.na, margin = 2, negate = TRUE)